1. Field of the Invention
This invention relates to reaction of a silicate and polycarbinol, then recovering the product as small particles useful as reinforcement in polydiorganosiloxane.
2. Background Information
Improved mechanical properties of blends made from polyvinylalcohol (PVA) and polydiorganosiloxane are reported in Japanese applications No. 38347/78, 99987/80, and 73059/82. Improved properties are obtained when silica filler is included as a reinforcing filler.
Chemical modification of PVA with a silylating agent is known as in U.S. Pat. No. 4,617,239, issued Oct. 14, 1986. This patent discloses a silicone containing PVA agents useful in paper coatings. One method introduces a silicone moiety into a PVA by post modification with a silylating agent or addition into a derivative of PVA that contains carboxylic groups such as partially saponified polyvinyl acetate followed by saponification of the residual acetates. Another method saponifies a copolymer of vinyl ester and silicone-containing olefinic unsaturated monomer followed by addition polymerization.